Thanks to the combination of high-resolution transrectal ultrasound and the "Biopty-Gun", it has now become possible for the first time to obtain multiple punch biopsies of the prostate, painlessly and with few complications. "Mapping" of the prostate by 6 randomized punch biopsies permits an evaluation of the sensitivity and specificity of such screening procedures as digital rectal examination (DRE), prostate-specific antigen (PSA) and transrectal ultrasound (TRUS). In addition, randomized biopsies provide reliable information about prostatic carcinomas with a significant volume. The indications and efficacy of the various diagnostic methods are discussed in detail.